Well tool



March 2 1926. 1,575,120

G. B. I OUDRBACK WELL TOOLA Filed May l2 l 1924 Y PWM lttorrg.

l To all whom it may concern.'

Patented Mar. 2, 19726.

ienoaen B. Lounamcx, or. COMPTON, caLIFoaNra.

'WELL TOOL.

Application and lay 12, 19u. serial 1ro. 712,735.

Be it known that I, GEORGE B'. Lourma- BACK, a citizen, of the UnitedStates, residing at Compton, in the county Los Angeles and State ofCalifornia, have invented a new and useful Well Tool, of which aspecification is set forth below.

In this specification, and the accompanying drawing, I shall describeand show a preferred form of my invention, and specifically mentioncertain of its more important objects.- I do not limit myself to the`forms disclosed, since various changes and .adaptations may bemadetherein Awithout departing from the essence of my invention ashereinafter claimed; and Aobjects and advantages, other than thosespecifically men'- tioned, are included rwithin its scope.

My invention relates to well tools and .particularly tobites adapted fordeep well drilling, andamong its salient objects are;-

first, to provide a simple and convenient means for adjusting theelective drilling gauge of such a bitto compensate for wear,withoutremoving the tool from the dr1l1 hole; second, to supply anautomatic cutterretracting device, permitting the withdrawal of the toolfrom a hole of smaller diameter than the effective drilling gauge; and,third to accomplish `the required gauge adjust- .ment by a slightraising and lowering of cross sections to the same scale as Figure 2,

taken on the lines 3-3, 4-4, etc., of Figure 1.

Similar reference numerals refer to similar parts throughout the severalviews.

For illustrative purposes I have Aselected a disk bit having a pair ofcutting disks 7 journalled on retractible arms 8. The arms project fromthe lower end of a longitudinally split tool body comprising the similarhalves 9 and 10. These halves are suitably recessed to provideaccommodation -free to slide` longitudinally therein,.but is' for theinterior working parts, and each -llas a longitudinal groove 11 to serveas a circulating-water course.

The upper ends of the body halves are ot smaller diameter 'than thelower, and form the neck 12. The halves are assembledx face to face bymeans of a wedge band 13 atthe bot-tom, an lintermediate cylindricalscrewed-on shell 14, a screwed-on -ring 15. at the top of the neck, anda pair of throughbolts 16 at the lower extremity. A wedge 17, suitablyseated on the exterior of body half 9, serves to tighten upthe wedgeband. It is retained in position by means of a deformed washer 18 andscrew 19.

Above cylinder 14 is a variably bored and interiorly slotted tubularmember 20, carrying a spring-packed stuffing box 21 at its upperextremity, and a similarv but smaller diametei` stufiing box 22 yat itslower -end. Member 2O is taper-screwed into the top end of'lcylinder 14,and is littedlv'vith a. longitudinally slidable splined plunger 23carrying a taper-screw pin 24 at its upper extremity. `The plunger hasan axial bore 25 and is normally kept protruding its full extent fromstuffingA box 21. by means of a compression spring 26. 'It is machinedto fit the various bores of member 20, and is prevented from turning inthe member by its splines 27. At its lower end the plunger .carried 'anpopen-bottom cylinder 28 having a pair of interior projecting lugs 29,serving be described.

The upper ends of disk arms 8 are into the body of the tool. They areretained therein by bolts 16 assl throu h wedge shaped slots in thearlins. I Ihe 'upprextremities abut against correspondingly shapedsockets in the body halves-,'tofresist the thrust. of the disks when thetool *is* cutting, and the wedge shaped slots permit the arms toswing-about their rounded ends to provide the variable adjustment of thecutting` diameter. The arms are held atthe desired 'angular positionwhen drilling by means of the square wedge-shaped head 30 of feed screw31. When the wholetool is lifted however, the arms` are free to dropdown upon bolts 1 6 and in so doing they free themselves from engagementb head 30, and retract toward the axis of t e tool.

In vFigure 1 the arms are shown in their -as a part of an escapementmechanism to v ion apart to increase the drilling diameter, and' Figure2 shows the position they assume when drilling the maximum size hole.AllVhen thus adjusted, however, the arms are still free -to drop downupon the through bolts when the tool is lifted, and in so doing theywill come together again as in Figure }1),1but in this case they willhang upon the o ts.

The feed screw 31 does not rotate, since it is vprevented from doing soby its square head. Its neck may also be made square if desired, insteadof round asshown. The screw is lowered by turning the flanged feed nut33. The `upper end face ofthe nut is made in the form of a radial-toothratchet 34, engageable by a similar face on the lower end 35 of a deeplybored operating spindle 36. The feed screw in its upper position isnearly wholly within the bore of the spindle, and the latter projectsabove Athe neck 12 of the body of the tool through a cupped leatherpacking washer 37. l

Power for operating the spindle and Vfeed nut is sup lied by apreviously wound-up torsion spring 38, contained in a recess of neck 12.One end of this spring is attached to the spindle and the other to oneof the body' parts. Its stored energy is released as desired to lowerthe -feed screw by means of an escapement comprising av head 39, havingtwo pairs of lugs 40 and 41 in -vertically spaced planes, working incooperation with lugs 29 of the yescapement cyllnder. Lugsv 40 and 41are in quadrature relation as shown, and torsion spring 38 turns theoperating spindle 90 degrees at each operation of the escapement.

The escapement is worked by alternately raising and lowering the plunger23. Fig-1 ure 1 shows the plunger in' its upper posi-4 tion where itisnormally held by spring 26. In this position the lugs 29 in theescapement cylinder engage lugs 40 of the escapement head as shownmostplainly in Figure 4. When the plunger is lowered lugs 29 disengage theupper pair of lugs' on the es' capement head and engage the lower pair41 after the spindle has revolved 90 degrees under the compulsion oftorsion spring 38.

Reaming blades 42 may be added to thc tool if desired and do notconstitute an essential part of the present invention. In place o theseblades, centering devices may pivoted cutters; a feed screw adapted foi"variably spacing said cutters; a torsion spring adapted for actuatingsaid feed screw; andra plunger adapted by reciprocation to cause saidspring to act.

2. A drilling bit comprising; pivoted disk cutters on a vpair of pivotedarms; a feed screw' adapted for variably spacing said arms; a torsionspring adapted for actuating said feed screw; anda plunger withinv thebit, protruding therefrom, adapted by reciprocationto cause said springto act.

3. A drilling bit comprising; a pair of pivoted cutters; a feed screwadapted for variably spacing said cutters; a torsion spring vadapted foractuating said feed.

screw; an escapement for controllingv thel action of said spring; and aplunger adapt' ed by reciprocation to operate said escapement.

4. A drilling bit comprising; pivoted disk cutters on a pair of pivotedarms; a feed screw adapted` for variably spacing saidv arms; a torsionspring adapted for actuating said feed screw; an escapement forcontrollino the action of said spring; and a plunger win ed byreciprocation to operate said escapement.

5. A drilling bit comprising; a pair of ypivoted cutters; a feed screwadapted for yariably spacing said cutters; a torsion spring -adapted foractuating said feed screw; an esca ement for controlling the action ofsai adapted by reciprocation to operate said escapement; said cuttersbeing ada ted for gravitational retraction when the bitis suspended.

6. A drilling bit comprisin pivoted disk cutters on a air of pivotearms; a feed screw adapted for .variably spacing said arms; a torsionspring adapted for actuating said feed screw; an escapement forcontrolling the action of said spring; and a plunger within the bit,protruding therefrom, adapted by reciprocation to operate saidescapement; said cutters being adapted .for gravitational retractionwhen the bit is suspended.

GEORGE B. LOUDERBACK.

thel bit, protruding therefrom, adapt?A spring; and ya plunger

